World War I vs. World War II

The First World War (WWI) was fought from 1914 to 1918 and the Second World War (or WWII) was fought from 1939 to 1945. They were the largest military conflicts in human history. Both wars involved military alliances between different groups of countries.

World War I (a.k.a the First World War, the Great War, the War To End All Wars) was centered on Europe. The world warring nations were divided into two groups namely ‘The Central Powers’ and ‘The Allied Powers’. The central powers group consisted of Germany, Austria-Hungary, Turkey and Bulgaria. The Allied powers group consisted of France, Britain, Russia, Italy, Japan, and (from 1917) the U.S.

World War II (a.k.a the Second World War), the opposing alliances are now referred to as ‘The Axis’ and ‘The Allies’. The Axis group consisted of Germany, Italy, and Japan. The Allies group consisted of France, Britain, the U.S., the Soviet Union, and China. World War II was especially heinous because of the genocide of Jewish people perpetrated by the Nazis.

Comparison chart

World War I versus World War II comparison chart

World War I

World War II

Period and duration

1914 to 1918; 4 years

1939 to 1945; 6 Years

Triggers and causes

Assassination of Archduke Francis Ferdinand of Austria in June 1914. Militarism, Imperialism, nationalism and alliance system.

Political and economic instability in Germany. The harsh conditions of the Treaty of Versailles Rise of power of Adolf Hitler and his alliance with Italy and Japan to oppose the Soviet Union

The Axis Powers (Germany, Italy, and Japan) and the Allied Powers (France, Britain, the U.S., the Soviet Union, and China)

Casualties

Estimated to be 10 million military dead, 7 million civilian deaths, 21 million wounded, and 7.7 million missing or imprisoned.

Over 60 million people died in World War II. Estimated deaths range from 50-80 million. 38 to 55 million civilians were killed, including 13 to 20 million from war-related disease and famine.

Genocide

The Ottoman Empire (Turkey) carried out genocide of Armenians.

German Nazis committed genocide against Jews and Romanis, people with disabilities, Poles, homosexuals, Jehovah's witnesses and Afro-Germans.

Methods of warfare

Fought from lines of trenches and supported by artillery and machine guns, infantry assault, tanks, early airplanes and poisonous gas. Mostly static in nature, mobility was minimal.

Nuclear power and missiles were used, modern concepts of covert and special operations. Submarines and tanks were also more heavily used. Encryption codes for secret communication became more complex. Germany used the Blitzkrieg fighting method.

Outcomes

The German, Russian, Austro-Hungarian and Ottoman empires were defeated. Austro-Hungarian and Ottoman empires ceased to exist. The League of Nations was formed in the hope of preventing another such conflict.

The war ended with the total victory of the Allies over Germany and Japan in 1945. The Soviet Union and the United States emerged as rival superpowers. The United Nations was established to foster international cooperation and prevent conflicts.

Post-war politics

Resentment with the onerous terms of the Treaty of Versailles fueled the rise of Adolf Hitler's party in Germany. So in a way, World War I led to World War II. The first Red Scare in the U.S. to fight communism.

There was a Cold War between the United States and Russia after the end of the Second World War until the collapse of the USSR (1947-1991). The wars in Afghanistan, Vietnam and Korea were, in a sense, proxy wars between the two nations.

Nature of war

War between countries for acquiring colonies or territory or resources.

Several alliances formed over the past decades were invoked, so within weeks the major powers were at war; as all had colonies, the conflict soon spread around the world.

This video from Yale explains the events that led to World War I:

Causes of World War II

The Versailles Treaty signed at the end of World War I not only lay the moral blame of the conflict on Germany but also forced the Germans to make huge payments to the victors of the war. France and Britain needed these reparations payments in order to pay down their own debts. But they were highly onerous, arguably unjustifiably so, and were deeply unpopular in Germany. Hitler seized on this growing resentment and promised to "undo this injustice and tear up this treaty and restore Germany to its old greatness". In fact, the payments demanded were so large that Germany was able to repay the final installment of interest on this debt only on October 3, 2010.[1]
The following causes of World War II are generally acknowledged:

Treaty violations and acts of aggression on various fronts.

Political and economic instability in Germany, combined with bitterness over its defeat in World War I and the harsh conditions of the Treaty of Versailles.

Rise of power of Adolf Hitler and the Nazi Party. In the mid-1930s Hitler began secretly to rearm Germany, in violation of the treaty.

Adolf Hitler signed alliances with Italy and Japan to oppose the Soviet Union

German invasion of Poland on Sept. 1, 1939

The following documentary delves into the causes of World War II:

Sequence of events

World War I

The sequence of events for World War I began in 1914 with Austria-Hungary declaring war on Serbia on 28 July 1914 in a bid to reassert its authority as a Balkan power. With war breaking out between Austria-Hungary on one side and Serbia on the other, Europe quickly fell back to the alliances nations had formed. Austria-Hungary and Germany were allies. Serbia was allied with Russia; as was France. Russia aided Serbia and attacked Austria. So Austria-Hungary was fighting in two fronts with Serbia and with Russia and consequently lost on both fronts. In a bid to aid Austria-Hungary against Russia, and fearing an attack from France, Germany mobilized its army and attacked France.

1915

The French, redeploying round Paris, together with the British, checked the now extended German armies on the Marne. In March and April 1915 British sea and land forces attacked the Dardanelles. The Turks countered both threats, causing the British to evacuate the Gallipoli peninsula at the end of 1915.

A joint Austro-German offensive at Gorlice-Tarnow (2 May 1915) unlocked Russian Poland and the tsar's shattered armies fell back

In 1915 the Allies agreed that simultaneous attacks on all fronts were the way to drain the reserves of the Central Powers

1916

On 21 February 1916 Germans attacked the Verdun salient; however this attack was stalled in June. Austrians' independent offensive against the Italians in the Trentino also stalled.

1917

Germany finally adopted unrestricted submarine warfare in February 1917, and in doing so drove America into the war.

1918

The Germans extended their front while reducing their strength by almost a million men. Simultaneously they continued to advance in the east, competing with their Austrian allies in the Ukraine and the Turks in the Caucasus. * The French counter-attacked in July and the British in August. Together with the Americans, they drove the Germans back in a series of individually limited but collectively interlocking offensives.

On 15th September the Anglo-French forces at Salonika attacked in Macedonia, forcing the Bulgars to seek an armistice by the end of the month.

The whole of the Central Powers' Italian front crumbled after the Austrian defeat on the Piave in June.

The German high command initiated the request for an Armistice on 4 October. After the war Germany claimed that the army was ‘stabbed in the back’ by revolution at home. The people of Germany and Austria-Hungary were battered by food shortages and inflation.

On 11 November an armistice with Germany was signed in a railroad carriage at Compiègne. At 11 a.m. on 11 November 1918 a ceasefire came into effect.

1919
A formal state of war between the two sides persisted for another seven months, until signing of the Treaty of Versailles with Germany on 28 June 1919

World War II

The war that broke out in 1939 was a war for the European balance of power. The immediate cause of the conflict was the German demand for the return of Danzig and part of the Polish ‘corridor’ granted to Poland from German territory in the Versailles Treaty of 1919. Poland refused to agree to German demands, and on 1 September 1939 overwhelming German forces launched the Polish campaign and defeated her in three weeks. Russia also invaded eastern Poland. Poland thus got divided into two parts. In March 1939 Britain and France had guaranteed Polish sovereignty, and in honor of that pledge first demanded that German forces withdraw, and then on 3 September declared war on Germany. America was committed by the Neutrality Acts of 1935 and 1937 of non-intervention in overseas conflicts.

This video presents a concise history of the events of World War II:

1940

German armies invaded Belgium, Luxembourg, and northern France and within six weeks defeated western forces.

Britain was able to resist German air attacks in the battle of Britain in August and September 1940, and survived a German bombing offensive (the ‘Blitz’) in the winter of 1940-1, but it was not possible for Britain to defeat Germany unaided.

On 10 June 1940 Mussolini's Italy declared war on Britain and France.

In December 1940 Hitler turned attention away from Britain and approved BARBAROSSA, the large-scale invasion of the USSR.

America started giving increasing economic assistance to Britain and China following President Roosevelt's pledge to act as the ‘arsenal of democracy’.

1941

BARBAROSSA was launched on 22 June 1941 when three million German, Finnish, Romanian, and Hungarian soldiers attacked the whole length of the Soviet western frontier. Soviet Union was shattered.

In North Africa, Commonwealth forces stationed in Egypt drove Italian armies back across Libya by February 1941

In Abyssinia and Somaliland Italian forces were forced to surrender by May 1941.

Italy's complete defeat in Africa was avoided only by Hitler's decision to send German reinforcements under Rommel, and the weak logistical position of Commonwealth forces.

The US navy became closely involved in the battle of the Atlantic in efforts to break the German submarine blockade of shipping destined for Britain. In March 1941 Congress approved the Lend-Lease Bill which allowed almost unlimited material aid, including weapons, for any state fighting aggression. In the autumn of 1941 this came to include the USSR, despite strong American anti-communism. Throughout 1940 and 1941 the USA tightened an economic blockade of Japan which threatened to cut off most Japanese oil supplies.

American actions provoked both Japanese and German retaliation. On 7 December 1941 Japanese naval aircraft attacked the American naval base at Pearl Harbor, followed by the rapid conquest of western colonies in south-east Asia and the southern Pacific.

On 11 December Germany declared war on the USA.

1942

Russia made a remarkable recovery and in November Germany and her allies attacking Stalingrad (now Volgograd) were cut off by a massive Soviet encirclement, URANUS.

In November 1942 at Alamein a predominantly Italian force was defeated by Montgomery.

The USA fought a largely naval and air war between 1942 and 1945, using its very great naval power to deploy troops in major amphibious operations, first in the Solomon Islands to halt the Japanese Pacific advance, then in TORCH, a combined American-British landing in Morocco and Algeria in November 1942.

A montage of World War II photos

1943

The entry of the USA signaled a change in the political balance of the war of great significance. German forces in Stalingrad surrendered in January 1943and by May 1943 Italian and German forces finally surrendered in Tunisia, enabling the Allies to mount the invasion of Sicily and then Italy. Italy sued for an armistice in September 1943.

1944

American economic might and political interests helped to bind together the different fronts of conflict, while America's worldwide system of supply and logistics provided the sinews of war necessary to complete the defeat of the aggressor states. A major intelligence deception operation and declining air power weakened the German response and by September 1944 German forces had been driven from France.

1945

German surrendered on 7 May 1945 following Hitler's suicide on 30 April.

A long-range bombing campaign destroyed the Japanese cities and most of the Japanese navy and merchant marine. America’s newest weapon, the atomic bombs were dropped on Hiroshima and Nagasaki in August 1945.

Soviet forces destroyed the Japanese army in Manchuria; Japan finally capitulated on 2 September.

War strategies

Many of the weapons that dominate military operations today were developed during World War I, including the machine gun, the tank and specialized combat aircraft. This is a great video that explains the military strategies and tactics used during World War I.

Outcomes

World War I

After the war, the Paris Peace Conference imposed a series of peace treaties on the Central Powers. The 1919 Treaty of Versailles officially ended the war. Building on Wilson's 14th point, the Treaty of Versailles also brought into being the League of Nations on 28 June 1919. In signing the treaty, Germany acknowledged responsibility for the war, agreeing to pay enormous war reparations and award territory to the victors. It caused a lot of bitterness.

Austria–Hungary was partitioned into several successor states.

The Russian Empire lost much of its western frontier as the newly independent nations of Estonia, Finland, Latvia, Lithuania, and Poland were carved from it.

World War II

The war ended with the total victory of the Allies over Germany and Japan in 1945. The United Nations was established to foster international cooperation and prevent future conflicts.

The Soviet Union and the United States emerged as rival superpowers.

Although the totalitarian regimes in Germany, Italy, and Japan were defeated, the war left many unresolved political, social, and economic problems in its wake and brought the Western democracies into direct confrontation with their erstwhile ally, the Soviet Union under Josef Stalin, thereby initiating a period of nearly half a century of skirmishing and nervous watchfulness as two blocs, each armed with nuclear weapons, faced each other probing for any sign of weakness.

The European economy had collapsed with 70% of the industrial infrastructure destroyed.

A rapid period of decolonization also took place within the holdings of the various European colonial powers. These primarily occurred due to shifts in ideology, the economic exhaustion from the war and increased demand by indigenous people for self-determination.